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DOI: 10.1021/nl2045952

Water micro droplets containing graphene oxide and a second solute are
shown to spontaneously segregate into sack-cargo nanostructures upon
drying. Analytical modeling and molecular dynamics suggest the sacks
form when slow-diffusing graphene oxide preferentially accumulates and
adsorbs at the receding air water interface, followed by capillary
collapse. Cargo-filled graphene nanosacks can be nanomanufactured by a
simple, continuous, scalable process and are promising for many
applications where nanoscale materials should be isolated from the
environment or biological tissue.